Zn²⁺ adsorption from wastewater using a chitosan/β-cyclodextrin-based composite membrane

Area of Science:

• Materials Science
• Environmental Chemistry
• Chemical Engineering

Background:

• Industrial wastewater frequently contains toxic heavy metal ions like zinc (Zn²⁺).
• Effective removal of these ions is crucial for environmental protection and human health.
• Existing treatment methods can be costly and complex.

Purpose of the Study:

• To synthesize a novel biomass-based composite membrane for zinc ion adsorption.
• To investigate the preparation conditions influencing the membrane's adsorption performance.
• To evaluate the adsorption efficiency of the developed composite membrane for Zn²⁺.

Main Methods:

• Synthesis of a β-cyclodextrin polymer (β-CDP) using β-cyclodextrin (β-CD) and citric acid (CA).
• Cross-linking of chitosan (CTS) with β-CDP to form a CTS/β-CDP composite membrane.
• Optimization of preparation conditions (temperature, acid concentration, solvent dosage, soaking time) in sodium hydroxide.
• Characterization using FTIR, SEM, and XRD; evaluation of adsorption capacity and rate for Zn²⁺.

Main Results:

• Optimal conditions yielded a maximum Zn²⁺ adsorption of 123.7 μg/g and an adsorption rate of 94.14%.
• The CTS/β-CDP composite membrane demonstrated superior Zn²⁺ adsorption compared to individual components.
• Characterization confirmed successful synthesis, increased surface roughness, amorphous structure, and improved recyclability potential.

Conclusions:

• The developed CTS/β-CDP composite membrane is highly effective for Zn²⁺ adsorption from simulated wastewater.
• This biomass-based material presents a promising, cost-effective solution for small-scale industrial wastewater treatment.
• The study highlights the potential for treating heavy metal ion contamination in wastewater.